1. Field of the Invention
This invention relates to a system for the biological control of plant pathogenic fungi in soil and more particularly to the use of the mycoparasite, Sporidesmium sclerotivorum, to control and destroy or eradicate the sclerotia of plant pathogenic fungi susceptible to Sporidesmium such as those of the genus Sclerotinia and Sclerotium cepivorum. The invention also relates to a novel method of producing the mycoparasite, Sporidesmium sclerotivorum.
2. Description of the Prior Art
Although the concept of biological control of plant disease microorganisms has been known for a number of years, there is no known relevant art regarding the mycoparasite, Sporidesmium sclerotivorum, because it has only recently been discovered.
A subculture of this mycoparasite can be obtained from the permanent collection of the Northern Regional Research Center, Science and Education Administration, U.S. Department of Agriculture, Peoria, Ill., U.S.A., 61604. Its Accession No. in this repository is NRRL 11437. As of the filing date of this application, progeny of the subject strain will be made available to anyone who requests the same. A taxonomic description of the mycoparasite is found in Mycotaxon 7, 275-282, 1978, which is herein incorporated by reference.
Coniothyrium minitans is a well known mycoparasite of Sclerotinia spp. and Sclerotium spp. and under controlled conditions has shown promising results in reducing the inoculum potential of these fungi. However, a field trial in soil naturally infested with S. sclerotiorum was only partially successful.